Currently, there is no commercially viable process for recycling and recovering the components used to manufacture alkaline and carbon zinc batteries, without resorting to the added incentive of the recycler being paid an additional fee for processing such batteries. There is, at present, a minimal amount of recycling of alkaline batteries wherein the zinc and manganese oxide mixtures recovered from such batteries are used as a supplement in animal feeds. No such recycling of carbon zinc batteries is performed, however. Only a small fraction of the alkaline batteries discarded each year are recovered in this way, with such processing only being practiced because of the processing fees paid.
About 85% by weight of all batteries is made up of these two types of disposable (non-rechargeable) batteries. The vast majority of such batteries are disposed of in landfills.
Carbon zinc batteries have a carbon rod as the cathode electrode, surrounded by manganese dioxide, with a zinc metal case for the anode. Alkaline batteries have a brass pin surrounded by zinc powder for the anode with manganese dioxide as the cathode and a steel case as the cathode electrode. An alkaline battery uses about 20% aqueous KOH as the electrolyte, while a carbon zinc battery uses aqueous ammonium chloride as the electrolyte. The relatively low value of the contents of these types of batteries has made it difficult for any recycled materials recovery process to be viable commercially. To date, it has been more cost effective to landfill these batteries, particularly the lower cost carbon zinc batteries, rather than recover the zinc and manganese from them.